Tube-dwelling sea flea • Ericthonius rubricornis

Left: a mass of tubes built by tube-dwelling sea fleas, attached to intertidal rock. Right: a tube-dwelling sea flea out of its tube. Photos by Jenn Burt.

IdentificationThis amphipod species may only be evident by a cluster of small greyish tubes attached to rock or other substrates. These tubes are used for protection, and only the head of this small brownish crustacean may be seen peeking out. ​Habitat & RangeThis species builds tube colonies to 15 cm across in the intertidal and subtidal. Reports of its distribution vary; according to Lamb and Hanby it is found in the eastern Pacific from northern Alaska to southern California. It is also reported on both sides of the North Atlantic.

Similar SpeciesA study in British Columbia's Strait of Georgia found the tube-dwelling sea flea as well as three other species of Ericthonius.